title: Outbreak of Group A beta hemolytic Streptococcus pharyngitis in a Peruvian military facility, April 2012.
abstract: Group A Streptococcus (GAS), or Streptococcus pyogenes, is a common cause of acute pharyngitis as well as other diseases. Closed populations such as those living on military bases, nursing homes, and prisons are particularly vulnerable to GAS outbreaks due to crowding that facilitates person-to-person transmission. This report details a large outbreak of GAS pharyngitis at a Peruvian military training facility near Lima, Peru, in April 2012. Initial findings showed 145 cases. However, as the investigation continued it was revealed that some trainees may have concealed their illness to avoid real or perceived negative consequences of seeking medical care. A subsequent anonymous survey of all trainees revealed at least 383 cases of pharyngitis among the facility's 1,549 trainees and an attack rate of 34 percent among the 1,137 respondents. The epidemic curve revealed a pattern consistent with routine person-to-person transmission, although a point-source initiating event could not be excluded. Laboratory results showed GAS emm type 80.1 to be the culprit pathogen, an organism not commonly implicated in outbreaks of GAS in the Americas. Barious unique and illustrative features of outbreak investigation in military facilities and populations are discussed.
authors.affiliation: Emerging Infections Department, U.S. Naval Medical Research Unit No. 6, Lima, Peru.
authors.forename: Mariana
authors.initials: M
authors.lastname: Ramos
authors.forename: Ruben
authors.initials: R
authors.lastname: Valle
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Reaves
authors.forename: Luis
authors.initials: L
authors.lastname: Loayza
authors.forename: Sofia
authors.initials: S
authors.lastname: Gonzalez
authors.forename: Maria
authors.initials: M
authors.lastname: Bernal
authors.forename: Giselle
authors.initials: G
authors.lastname: Soto
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Hawksworth
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Kasper
authors.forename: Drake H
authors.initials: DH
authors.lastname: Tilley
authors.forename: Carlos A
authors.initials: CA
authors.lastname: De Mattos
authors.forename: Jason R
authors.initials: JR
authors.lastname: Brown
authors.forename: David G
authors.initials: DG
authors.lastname: Bausch
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004196:Disease Outbreaks; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D058749:Military Facilities; D008889:Military Personnel / Q000706:statistics & numerical data*; D010568:Peru / Q000453:epidemiology; D010612:Pharyngitis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000302:isolation & purification* / Q000472:pathogenicity